Lock



LOCK

Filed Nov. 17, 1937 5 Sheets-Sheet 1 3nnentor C HARPE S SWIkENS 2 Z I(Ittorneg Oct; 17, 1939. Q w s 2,176,369

LOCK

Filed Nov. 17, 1937 '5 Sheets-Sheet 2 Oct. 17, 1939.

c SWILENS LOCK Filed Nov. 17, 1937 5 Sheets-Sheet 3 Zimaentor C \a fi sY ms Oct. 17, 1939. c, sw 2,176,369

LOCK

Filed Nov. 17, 1957 5 Sheets-Sheet 4 I) l W 0 WW//////I//I/////////////I C. SWILENS Oct. 17, 1939.

L0 CK Filed Nov. 17, 1937 5 Sheets-Sheet 5 Z5 27 26 J6 J7 Snnentor 1 CKarlem Sunbeam qttomeg Patented Oct. 17, 1939 UNITED STATES PATENTOFFICE 2 Claims.

This application is directed to a divisible subject matter disclosed inmy prior application filed April 12, 1935, Serial No. 15,997, which hasterminated in a patent dated December 8, 1936, No.

My invention relates to a combined lock and latching mechanism fordoors, preferably for use with dwellings, apartments, oflices, and thelike, and preferably of the mortise type variety where the'lock casingis mortised or otherwise seated in an opening formed in the door.

' The primary object of my invention is the provision of a lock andlatching mechanism which secures the door in locked position againstunauthorized opening or picking of the lock, and is adapted to afford amechanism of safety against unauthorized opening by the use of skeletonkeys, lock picks, and the like.

Another object of my invention is the provision of a locking mechanismfor doors in which the locking means is capable of being placed invarying positions whereby the locking mechanism can be actuated by a keyfrom one side of the look only, thereby reducing the opportunities touse g skeleton keys, lock picks or the like for unauthorized opening ofthe door, the locking mechanism being capable of being changed to adifferent position whereby the same key will lock and unlock themechanism from the'opposite side of 30 -'the' door to that justmentioned, but cannot operate the locking mechanism from the firstmentioned side. In other words, in the normal operation of the lockingmechanism the locking apparatus is operable from one side of the lookonly.

35 Another and further object of my invention is the provision oflocking mechanism adapted to be actuated by the usual key and which,when placed in proper position in the key post, rotates the key post anda part of the actuating (l-mechanism without aligning the tumblersproperly, thereby allowing the locking post to be operated freely butwithout the danger of twisting a key off in the lock or breakingportions of the locking mechanism if excessive force is applied to 45the key.

A further object of the invention is a combined latching and lockingmechanism having operable means therefor, preferably in the form of the50 usual door knobs, with a connecting shaft extending therethrough, andwhich is so constructed that when the latch is in locked position theknobs are freely rotatable Without putting undue strain or force uponthe locking mechanism or 56 allowing injury to be sustained by thelocking mechanism if undue force is applied to the looking means.

A still further object of my invention is the provision of a lock whichprovides means for slightly altering the position of the locking tum- 5blers thereby altering the lock in such manner that the effective use ofthe key for opening it is destroyed and making it necessary to obtain anew key which is used for opening the look, as a protection against lostkeys and the like. 10

Still another object of my invention is the provision of a door lockhaving a latching mechanism which is adapted to be used with right orleft swinging doors, the door latch being reversible in the casing sothat its angular disposed face 15 will engage a striking plate usuallysecured to the door frame.

Another and further object of my invention is the provision of a lockcasing having the locking parts positioned therein to which access canbe 20 had from one side only, preferably the inside if used upon adwelling, so that it is impossible to obtain access to the tumblers orother operating parts for the purpose of picking or otherwiseunauthorized opening the lock.

Another and further object of my invention is the provision of a simple,efficient lock Which is cheap to manufacture, and which provides ameasure of security against unauthorized opening or picking of the lock.

These and other objects of my invention will be more fully and betterunderstood by reference to the accompanying sheets of drawings, in WhichFigure 1 is a side view, partially in section, partially in elevation ofthe lock installed in a door, with the locking bolt in locked position;

Figure 2 is a view similar to Figure 1 with the parts in the samerelative position except that the locking bolt is in unlocked position;

Figure 3 is a View similar to Figures 1 and 2, in which the lockingmechanism has been shifted to a different position in the lock casingand showing the locking bolt in unlocked position;

Figure 4 is a vertical sectional view on line 4-4 5 of Figure 1;

Figure 5 is an elevational view of one of the knobs with the outer shellremoved;

Figure 6 is a sectional View on line 66 of Figure 1;

Figure 7 is a detailed view, partially in elevation and partially insection, on line ll of Figure 1;

Figure 8 is a perspective View of one of the tumblers used in the lock;

Figure 9 is a transverse sectional view on line 99 of Figure 1; and

Figure 10 is a detailed sectional view on line lit-I5 of Figure 1.

Referring now specifically to the drawings, and in which like referencecharacters refer to like parts throughout, a door I0 is shown having alock casing designated as a whole as H located therein. The lock casingit comprises two members placed in side to side relation with eachother, one member having a side wall l2, a top wall 13, a bottom wallI4, and a front wall l5 having the usual latch and locking bolt openingstherein, the side, top, bottom and front walls being formed integrallywith the side wall l2, as is the usual practice with lock casings ofthis type. The other member comprises a cover plate l6 having a rearwall portion l'l integrally fromed therewith, and which is adapted tofit against the edges of the wall portions of the side wall 12. A guideblock i8 is mounted against the side wall [2 at the upper side thereof,and a lower guide block i9 is mounted against the side wall H2 at thelower side thereof, both guide blocks abutting against the front wallI5, with hollow studs 20, 20 being provided toward the rear side of theside wall l2 which are internally threaded and have'screws 2 9, 2|positioned therein, with similar screws extending into the blocks l8 and9 for holding the two members of the casing together. A face plate 22 isprovided which is fitted against the front wall l5 and which is securedto the easing by any appropriate fastening means as by screws extendingoutwardly through ears 23, 23 integrally formed with the wall of thecasing or secured thereto in any manner that may be desired.

In the lower part of the casing a locking bolt 24 is mounted in slidingengagement with the lower guide block l9,and upon guide lugs 25, 25spaced apart from each other and secured to the locking bolt 24 in anyapproved manner. The rear end 25 of the locking bolt is bifurcated andhas a star wheel 2'! having teeth 28, 28 thereon, mounted upon a pin 29extending through the bifurcated portions of the rear end 26 of thelocking bolt 24. A movable friction lug 3B is mounted in the bifurcatedend 25 of the locking bolt 24 having a pin 3i secured thereto, with anopening 32 extending longitudinally of the locking bolt adapted toreceive a spring 33 which surrounds the pin 3! for the major portion ofits length. The spring 33 forces the friction lug in engagement with theends of the teeth 28 on the star wheel 2 1, the ends of these teethbeing provided with angular ends as will be noted, in order to hold thestar wheel 2t against easy rotation. Mounted in the locking bolt 24 is apivotally mounted locking arm 34 having a pin 35 extending therethroughand forming a mounting for the locking arm 34. The locking bolt 24 has atransverse extending bore 35 formed therein within which a pin. 3? ismounted having a spring 38 extending therearound, the head of the pinextending under one end of the locking arm 34 and normally tending tohold the locking arm 34 in position against a stop 35 which ispositioned by means of a pointed screw extending through the side of thelocking bolt 24, and providing means by which the locking arm 34 is heldin a plurality of adjusted positions. The transverse hole 555 extendsentirely through the locking bar 24 and is of sufiicient size toaccommodate the pin 37 and spring 38, but is decreased in size at thelower side of the bolt 24, thereby forming an annular shoulder tosupport the spring 38. The pin 37 in both the locked and unlockedposition of the locking bolt 24 is forced downward by the locking arm 34into holes l9a, liia, and forms one of the means by which the lockingbolt 24 is held against movement. The locking arm 34 extends upwardlyand rearwardly from the looking bolt and has cam surfaces 4| on thelower side thereof, with arcuate recesses between the cam surfaces 4|for purposes hereinafter described, and has a locking pin 42, preferablyrectangular in shape, for engagement with the looking tumblershereinafter described, extending therethrough and projecting therefromon each side.

Mounted in the casing I I is a block 42a, which is mounted on guides 43and 44 respectively, placed against the side plate I2, with a threadedopening therethrough within which a worm 45 is mounted. The worm 45 hasa shaft 46 extending therethrough, preferably rectangular in crosssection on the inner end, on the outer end of which a thumb button 41 isplaced, the button having an annular channel 48 extending therearound.The shaft 46 has a spring 49 extending therearound seated inside of theworm member 45, and has a thimble 5i] thereon the inner end of whichforms an abutting member for the spring 49, the opposite end of thespring abutting against a shoulder formed on the inner flare of the worm45, the spring 49 being normally held in compressed position within theworm 45. Mounted in a recess in the face plate 22 is a sliding latchmember 5! having a spring 52 therein adapted to engage against a pin 53in the face plate 22, with a finger piece 54 extending outward at thelower end thereof which extends through a recess in the face plate 22.The upper end of the member 5| is adapted tov be seated in the annularchannel 48 in the normal position of the lock with the heads countersunkin the face plate 22 so that a smooth surface is presented, but when themember 5|. is pushed downward, the spring 49 forces the shaft 45 outwardso that the worm member 45 can be rotated, thereby shifting the block420:, and tumblers to different positions, as will be hereinafterdescribed.

The block 42a at the lower side thereof has a rearwardly extendingportion 55, and a tumbler supporting member 56 mounted in an openingformed in the block 42a in the lower side thereof. The member 56 has aslot 5'l therein within which a spring 58 is positioned which seatsagainst a pin 59 extending through the slot 5! and the member 42a. lhemember also has a slot at one side which extends over the base portionof the member 55 and in sliding engagement therewith so that this memberis normally held in the position shown in Figure 1, but may be slightlyretracted against the pressure of the spring 58 during the operation ofthe lock.

The member 56 has a depending portion 65 projecting below the member42a, with a plurality of tumblers 6 I, 66 pivotally mounted thereon bymeans of a pin 52, the tumblers six in number as shown being mountedthree on one side of the depending portion 60 and three on the otherside in side to side relation with each other. The tumblers 66 each havesprings 64 secured thereto which are adapted to engage under the portion55 of the block 42a, and have rectangular openings therein, the frontopening being designated as 65, the intermediate opening .projection '12engages in the star wheel 21.

as 66, and the rear opening as 61. Connecting the openings 65 and 66 isa slot 68 which is narrow at its front portion and diverges outwardly,terminating in the recess 66, with shoulders adjacent the recess 66which are adapted to engage the transversely extending locking pin 42mounted in the rear end of the locking arm 34. The locking pin 42 isadapted to engage in the openings 66 and 61 in the unlocked and lockedpositions of the locking bolt 24 shown in Figures 1 and 2, and in theopenings 65 and 66 in the unlocked and locked positions of the lockingbolt 24 as shown in Figure 3.

'A key post 69 is mounted in the lock casing ll having a key slot HItherein, and comprising annular outer portions adapted to engage againstthe side plates l2 and I6 respectively, with a central annular portionbeing provided having a projection 12 thereon. In its upper position theprojection 12 is adapted to engage the under side of the locking arm 34and passes over the cam surfaces 4|, and normally in either the lockedor unlocked position of the door is in register with one of the arcuaterecesses adjacent the cam surfaces 4|, this position being necessary inorder to properly align the key slot in the annular portions of the keypost 69 with the key slot in the plates I2 and N5 of the lock casing Ii,in order that a key may be inserted and withdrawn from the key post 69.As the key post 69 is rotated, the projection 12 also engages the teeth28 on the star wheel 21 for the purpose of operating the locking bolt24. If the locking pin 42 in the locking arm 34 is free of the lockingtumblers, the locking bolt 24 slides easily in its position in thecasing and can be moved to locked or unlocked position .as the key postis rotated and the projection 12 engages in the star wheel 2?. If,however, when the key is inserted in the lock the locking pin 42 is inengagement with any of the tumblers, the

key post rotates in the lock casing, in which case the star wheel 2? isrotated by the key post, the locking bolt 24 thereby not being actuatedby the key, the key post rotating freely in the lock casing, the onlyresistance thereto being that created by the friction exerted on theouter surface of the projection 12 as it passes over the cam surface 4|on the rear end of the locking bar, and the frictional resistanceproduced by the friction between the friction lug 30 and the ends of theteeth 28 on the star wheel 2'1.

If, however, as the key is rotated in the key post the key aligns thetumblers in such manner that the transversely extending locln'ng pin 42in the rear end of the locking arm 34 is free of the edges of therectangular shaped transversely extending openings in the tumblers 5|and in alignment with the longitudinally extending slots therein, thelocking bar is thereby released as the The friction created between theends of the teeth 28 and the member 33 is suilicient to overcome theresistance of movement of the locking bolt 24 andthe locking bolt 24 ismoved into locked or unlocked positions as may be desired.

With respect to the position of the parts shown in Figure 2, when it isdesired to operate the lock, the key is inserted in the locking post 69which, in the normal position has the key slot extendingdownward, inwhich position the key is rotated in a clockwise direction when it isdesired to look a door. With the first movement of rotation of the keypost 69 the member 12 is moved out of the arcuate recess adjacent thecam surface 4| on the under side of the rear |9a in the guide block l9.

end of the locking arm 34, in which position the springs 64 push thetumblers down until their lower sides rest on the barrel portion of thekey post (shown in Figure 4), and the locking arm 34 is pushed into theposition where it rests upon the end of the pin 39 by the action of thespring 38 which also lifts the pin 3? out of the rear hole Continuedrotation of the key post 69 through the operation of the key brings theprojection 72 into engagement with the star wheel 2! and at the sametime the key comes into engagement with the under side of the tumblers6|, lifting all of the tumblers and aligning them until the locking pin42 is disengaged from the upper side of the recess 66, and in alignmentwith the slots 68 in the turnblers. In this position the locking bolt 24is moved forward by combined rotation of the key post, and continuedrotation of the key brings the projection 12 up into engagement with theunder side of the locking arm 34 along the camming surface, which ineffect raises the locking arm 34 slightly and also lifts the tumblers.The tumblers are shifted forward slightly as the locking arm 34 movesabout the pin 35 slightly shifting the tumbler supporting member 55, inwhich position the bolt is projecting from the lock in locked position.As the rear end of the locking arm 34 is lifted, its front end forcesthe pin 3'! into engagement with the guide block i9 and into the fronthole |9a therein, which with the engagement of the locking pin 42 in thetumblers securely retains the locking bolt 24 in position. Due to thelifting of the rear end of the locking arm 34 the whole lockingmechanism is placed under spring tension by the action of the springs 64on the locking tumblers and the spring 58 in the block 42a.

If, however, the key post should be rotated further so that theprojection F2 is out of engagement with the locking pin, then thesprings on the tumblers would force the tumblers down so that thelocking member 42 would still be in engagement with the tumblers and notbe released therefrom.

It will be understood, of course, that the key, after the lockingoperation, is removed from the lock and when it is desired to unlock thedoor to which the lock is secured, the key is inserted in the lockingpost and turned in a counterclockwise direction when the reverseoperation takes place, the tumblers properly aligned and the lockingbolt withdrawn.

When it is desired to set the lock for operation of the key on the sideopposite to that hereinabove described, the finger piece 54 is pusheddownward against the spring 52, releasing the shaft 46, which is forcedoutward to dotted position shown in Figure 6. The worm 45 is rotated sothat the lock 42a is drawn toward the forward edge of the casingcarrying with it the tumblers 5|, this operation taking place preferablywhen the lock is in unlocked position, thereby drawing the locking bolt24 forward at the same time. The key is thereupon inserted and uponbeing turned in a clockwise direction actuates the turnblers andwithdraws the locking bolt. The shaft 46 in the meantime is pressed backinto position in the recess in the face plate 22 and the door is inposition to be locked after being closed, if desired.

The same key is used for operating the lock from either side of the lockcasing, but due to the cutting of the tumbler recesses in the key thelocking mechanism cannot be actuated from both sides when the lockingtumblers are in the.

same position. In cutting the tumbler slots. in thekey the same generalrelationship must be maintained, that is, say No. l tumbler from oneside is lifted a predetermined distance to release the locking pin 42,when the key is reversed it must lift/N0. 6 tumbler the proper distance,taking into account the fact that the key in lifting the tumblersactuates them from two positions ,With respect to the radius of movementof the M tumblers about their axes of movement in the pin 62. In otherwords, the tumbler recesses in the key are out to raise the tumblers inproper relationship. with each other depending upon which side ofthelocking arm 34 they are positioned. In this manner the key willoperate only from. one side of the look at any particular setting.

A latch i3 is mounted in the upper side of the 2 casing, having a slot Mextending longitudinally thereof within which a spring 15 is mounted. Apost 16 is provided having a projection at one side thereof adapted tobe received into the spring 15, the post 16 being secured to the sideplate H2 in zggany approved manner. The rear end of the latch 13isU-shaped, the legs thereof being bifurcated, and has pins Ti, H locatedadjacent the end of the U-portions, upon which suitable rollers aremounted between the bifurcated portions of each 3021-;f the legs forengagement with the cam portions 18 of a latch actuating member 19,having a square opening therein adapted to receive an operating shaftextending from the operating knobs, so that a turning movement of themember l9 causes the cam portions to withdraw the latch it into thecasing ll. One side of the latch 73 at the outer end thereof isangularly disposed for engagement with a striking plate and may beremoved from the casing and its 41);; position reversed, with theangular side toward the opposite side to that shown in the drawings,thus enabling the lock to be used on either right or left hand doors.

A shank 89 is provided having a squared end 45;, portion 8i which fitsinto the squared opening in the member 79. On the outer end of the shankis a knob shell 82 having a transverse plate 83 extending thereacross,with a pair of bars 84, 84 also extending across the knob shell,

50.; with a pair of cam members 85 and 86 being provided which areadapted to engage the rectangu lar shaped end of a shaft 81; The shaft87! extends through the knob shank BBand into another knob shank 38 atthe opposite side of the 55%; door and into a knob 8d, preferably madeof two shell sections similar to the sections heretofore described butwithout the cam members therein. The shaft Bl has a key-Way 9% at oneend thereof with an annular collar 9i thereon adjacent to 60;;plate 83,which holds the shaft in fixed relation in the knob shell 3'2. The knobshank has a projection 92 adapted to fit into the key-way 99 in theshaft 8'5 so that the knob and knob section 88 are held against rotationon the end of the 65's shaft 87, and a turning force applied to the knobtends to rotate the shaft 8?.

Mounted in the cam members BEand 86 in the knob section 82 is a pair ofsprings 93, 93 respectively, which exert their pressure upon the mem-IOGbers 85 and 35 and hold these members into engagement with therectangular shaped end of the shaft 8'! so that the knob sections 82 and34 can be turned upon the shaft against the resistance of the springs93, which resistance is sufficient unto overcome-the resistance of thespring in the. latch 13. Mounted in the lock casing is a locking member94' having a shoulder 95 thereon and having a pin 96 at its oppositeend'to' provide pivotal mounting for the member 94-; and in the oppositeend a slot is formed in which a 5 spring 91 is positioned adapted'toengage againstv a pin 98 in the side plate l2, which pin extends intothe slot in the end of the member 94. A crank member 99 is providedhaving a pin I00 therein, the crank member being mounted bem: tween theside plates i2 and IS with a squared opening [0| therein having a pinH32 adapted to form a stop for the crank member 99 in the position ofthis. member as shown in Figures 1 and 2 of the drawings.

In encasing the lock in the door IE] the usual escutcheon plates I03 andNM are provided, one of which has studs H35, H15 inserted therethroughand passing through the door it] to the opposite. side of the door wherethey are adapted to receive m; screws I65, I06, preferably on the innerside of the door which prevents unauthorized removal of the escutcheonplates. A button I01 extends through one of these plates having asquared shaft I08 thereon which is adapted to be received in the squaredopening of the member 99 for operation of this member to bring thelocking member 94 up into position where it engages the rear end of thelatch member 73, as shown particularly in Figure 3. This provides anadditional safeguard for locking the latch member 73 and when in thisposition the door knob 89' on the outside of the door may be rotated, inwhich case the springs 93 are compressed, allowing the shaft 81 to turnrelative to the cam. members 85, 86, thereby forming a loose knobmounting which prevents any turning force being applied to the outsideknob S9 which might break some operating parts of the lock or the like.When the latch member 94 is dropped down r. so that it clears the end ofthe latch member, the springs 93 overcome the resistance of the springl5 mounted in the latch 73, the latch can be freely operated by means ofturning the knobs in either direction for the purpose of opening andclosing.

Suitable key guides ms, H39 are placed in the escutcheon plates H13 andE04, having key slots therein in register with the key slot in the post,through which the key is inserted for engagement with the key post andwhich serves to prevent access to the key post except through the narrowslots in the key guides, thereby prevent ing unauthorized access to thelocking parts.

In applying the lock to a door, the key guides H39, H19 are first placedin the escutcheon plates by removing the washers H0 from the barrels ofthe key guides I09, placing the barrel portions through the plates,placing the washers HE], H0 over the inner ends thereof, and thenpassing 50 screws in an outward direction through thewashers Hi3 andinto the barrel of the key guides, thus effectively securing these keyguides to the escutcheon plates. The escutcheon plates have socketsformed therein for the reception of the knob shanks, which have annularmembers H I, I l I on the ends thereof of larger outside diameter thanthe shank openings in the escutcheon plates. Screws l |2-pass throughthese annular members III and into the door knob 70. shanks so that thedoor knobs are held firmly against removal from the escutcheon plates.The knob shanks are secured to the escutcheon plates prior to theapplication of the escutcheon plates to the door l0, and when appliedhave the. 1| a screws I06 inserted from the inner side of the door, sothat unauthorized access to the lock or any of its parts after it isapplied to a door is reduced to a minimum.

The operation of my improved lock it is believed will be quite fullyunderstood from the foregoing description. I prefer to depend upon thelatch locking mechanism for the locking of the door against unauthorizedmovement from the inside, and therefore in operation the member I01 ispreferably adapted to be mounted on the inside of the door. When it isdesired to lock the door, this member is turned in such manner that thebell crank member 99 is turned upward so the pin I09 lifts the lockingmember 94 up into engagement with the end of the latch 13. In thisposition the latch is held against retraction and if an attempt is madeto open the door either of the knobs rotate without moving the latchmember out of engagement with the door casing. In this position, if itis desired to lock the door after passing through it, the key is used,in which position the tumblers are properly set for operation of the keyfrom the opposite side of the door on which the member I! is mounted.This adjustment is made by releasing the shaft 46 and rotating the worm45, shifting the tumblers to proper position so the key will operate thedoor from the proper side and the door is locked by use of a key.Thereafter the key is inserted from the outer side of the door and canbe used to unlock it by the simple operation of rotating the key andthrowing the locking bolt 24 into withdrawn position.

In case these operations are reversed, the face plates I94 are reversedwhen the door is installed, and the tumblers set in such manner thatthey function in a different location so that the locking mechanism canbe used with either right or left hand doors.

While I have described more or less precisely the details ofconstruction, I do not wish to be understood as limiting myself thereto,as I contemplate changes in form and the proportion of parts and thesubstitution of equivalents as circumstances may suggest or renderexpedient without departing from the spirit or scope of my invention.

What I claim as new is:

1. In a door lock having a spring-projected and manually retractablelatch bolt, wherein means is manually operable at the inner side of thedoor for releasably locking the latch bolt in projected position,wherein inside and outside knobs have shanks journaled at opposite sidesof the lock, and wherein the shank of the inside knob is operativelyconnected at its inner end with the latch bolt, a shaft journaled in theshank of the inside knob and keyed to the shank of the outside knob,said shank of the outside knob being free of direct operative connectionwith the latch bolt, and a clutch device within the inside knob whichgives an operative connection between said shaft and said inside knobwhen the latch bolt locking means is released and which permits turningof said shaft by the outside knob relative to the inside knob when thelatch bolt locking means is in locking position.

2. In a door lock having a spring-projected and manually retractablelatch bolt, wherein means is manually operable at the inner side of thedoor for releasably locking the latch bolt in projected position,wherein inside and outside knobs have shanks journaled at opposite sidesof the lock, and wherein the shank of the inside knob is operativelyconnected at its inner end with the latch bolt, a shaft journaled in theshank of the inside knob and keyed to the shank of the outside knob,said shank of the outside knob being free of direct operative connectionwith the latch bolt, a clutch device within the inside knob which givesan operative connection between said shaft and said inside knob when thelatch bolt locking means is released and which permits turning of saidshaft by the outside knob relative to the inside knob when the latchbolt locking means is in looking position, said clutch device includinga rectangular end on said shaft, a pair of spaced bars extendingdiametrically of and rigidly secured to and within said inside knob, cammembers slidably mounted within said inside knob between said spacedbars and at opposite sides of said rectangular end of said shaft, andsprings mounted within said cam members and bearing against the wall ofsaid inside knob for urging said cam members in engagement with saidrectangular end of the shaft.

CHARLES SWILENS.

